Gear Regulations/Tips for 2009 "Junior (17/18)" Racing? Anyone know, URGENTLY!!!

Home:Ballyhoura

Hi there, I am about to buy a bike and I plan on racing "Junior" next year. I would like to change the bits before using them so as not to be left over with useless used bits! Therefore I need to know urgently. My old bike had a 53/39 chainset and a 12-26 cassette which is the same as what is currently on the new bike. I found I needed a slightly lower gear (for climbs) and that the top gear wasn't needed (even for descending).

The bike is a 2008 Trek 1.5 (9speed double chainring version) and the category is Junior (Age 17/18).
Any help, tips, opinions and advice would be greatly appreciated! Thanks

I just came across on Cycling Irelands "Rules and Regulations" download that:

"Junior riders shall be restricted to a maximum gear roll out of 7.93 meters being the distance travelled by one crank revolution"
What does this mean gear wise?

Freddy687

Your Local Bike shop should be able to help you on this.
But as always Sheldon has the answers.
A 53 chainring with a 14 sprocket on the back is 8 meters. Just over the limit, which will mean you would have to stop at a 15 sprocket or 7.4 meters. This is a good bit beow the limit if you are racing.
A compact setup, 52/34 would allow a 14 sprocket, that gives you 7.8 meters.
The compact would also give a lower gearing for climbing, 2.7 meters Vs 3.2 meters, for your 26 sprocket.

http://www.sheldonbrown.com/gears/

http://www.machinehead-software.co.uk/bike/gears/gear_calculator.html

Mr. Skeffington

Hello Ballyhoura,

When I raced as a junior I took the stock cassette off the rear wheel with a chain whip and cassette tool. Then there are three screws that hold the cassette together, unscrew these and all of the sprockets and spacers will come apart. You then need to remove all of the sprockets lower than 15 teeth if you have a 53 front chainring to comply with the gearing ratio.

So say if you have a 12 - 25 cassette you will need to remove the 12, 13 & 14 teeth sprockets and start the gearing with a 15, making up the 3 sprockets that you removed with other sprockets. You should be able to buy individual sprockets from your local shop.

The other way to comply is to tape off the sprockets below 15 teeth with insulation tape and to restrict your rear derailleur from going into these sprockets.

Attached is an extract from another website which has a good explanation. If you need any further information please let me know.

2.2.024 For Junior Men and Junior Women, the authorized maximum chain gear ratio is 7.93 metres.



What does this mean?



When the bike is in the largest gear (big ring on the front, smallest gear on the back) it must travel less then 7.93 m when the pedals are turned exactly one full circle. This is tested by doing what is called a "roll-out". At the race, the commissaire will shift your bike into the largest gear available (biggest front, smallest back), and then roll it backwards watching one pedal. When the pedal goes around exactly one time, the distance will be marked. If it is more than 7.93 meters the bike will be illegal, and you will not be able to ride. At the end of the race the same check will be done, and if your bike fails, you will be disqualified.



So how do I comply?



The best way to insure that you bike will pass the test is to make sure that your "big ring" has 52 teeth, and that your smallest rear gear is 14 teeth. This combination is by far the most commonly used. In large, junior-only races, the neutral support mechanics will assume that you have this set-up if you need help with a flat or require other mechanical support during a race. These are standard parts that are readily available from your local bike shop, and should be provided at no extra cost on a new bike.



The other way to pass the test is to "block out" some of the gears on the back. If you have a 52 tooth "big ring" on the front you must block off all gears smaller that 14 on the back. If you have a 53 tooth "big ring" you must block off all gears smaller than 15. The best way to do this is to adjust the limit screw on your rear derailleur to prevent the use of the smaller gears. Some commisaires may also require you to make the illegal gears unusable by wrapping them with tape and/or cable ties. Remember that your bike will be checked after the race – if the adjustments slip during the race, or if you get a spare wheel that has different gearing, you could be disqualified.

Mr. Skeffington

I would not reccomend a compact chainset for junior competition. Keep your 53 - 42 at the front and make up your cassette with 15, 16, 17, 18, 19, 20, 21, 22, 23 & 24 if you have 10 speed rear mech.

Home:Ballyhoura

Hi there, thanks for your help! Its a 9speed rear mech and I currently have a 26 as my smallest gear (biggest cog) on the back, but I think I could do with a lower gear (maybe 27) for climbing Cratloe hill near my house. I find that when in the saddle in my smallest gear, my legs are barely turning and I have to get out of the saddle quite a bit if I am to make it up the hill at all!

If I was to keep the front chain rings as they are (53/39), I would need a 15-26 on the rear (I would prefer a 15-27, but do they make these anyway?)
If I was to put a 52 chain ring on the front (52/39), I would need a 14-26 (preferably 14-27) on the rear!
Is there anywhere that sell these online? The closest thing I found was a 14-25 at CRC http://www.chainreactioncycles.com/Models.aspx?ModelID=387 but this really wouldn't suit me! Do Shimano make these size cassettes or will I have to get one made up by my bike shop? On the other hand, would it be easier to get a smaller inner chainring (than 39), or is this possible?

Thanks again for all your help!